A clock provided to various cells in a multi-cell computer system may be referred to as a single point of failure because, when the clock fails, all cells using the clock fail. Further, in situations where clock redundancy is desirable, distributing redundant clocks from a clock source to various cells can add expense, pin counts in a chip, etc. To solve such problems, one solution uses a clock source for each cell, resulting in independent clocks from different clock sources. However, because of different sources, the clocks are no longer synchronous, or drift. That is, they assert different periods. In critical applications, even a small clock drift is not acceptable, and synchronizing these independent clocks to eliminate the drifts can require complicated mechanisms.